module;
#include <type_traits>

export module Code_19_8_4;

template<typename T, typename = std::void_t<>>
struct IsClassT : std::false_type {}; //primary template: by default no class

template<typename T>
struct IsClassT<T, std::void_t<int T::*>> : std::true_type // classes can have pointer-to-member
{
};

export
namespace Code_19_8_4 {

    void run()
    {

    }
}